Self-induced photogenic seizures in a child with severe myoclonic epilepsy in infancy: optical investigations and treatments.

In a 2-year-old patient with severe myoclonic epilepsy in infancy, we studied self-induced photogenic seizures using optical filters and blue-tinted contact lenses. The patient induced absences and/or myoclonic jerks by two kinds of behaviors: flickering hand movement (FHM) and forced eye closure (FEC). The placebo inhibitory effect on FHM by a blank goggle frame indicated that acquisition of learning affected the frequency of FHMs per se. Optical studies suggested that the degree of absorption from approximately 600-700 nm might determine the inhibitory effect of filters on FHM. Investigations using contact lenses showed that blue-tinted lenses gradually reduced photosensitivity and inhibited FHMs.